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MYOG: 3mil Plastic Tarps

Practice makes perfect: using polyethylene to prototype designs means I can spend less and try more variations before sewing a final product in technical materials.

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by Jerry Adams | 2011-02-08 00:00:00-07


MYOG: 3mm Plastic Tarps - 1
I have made several versions similar to this. In my three nights under this, it rained really hard with strong wind one night. The only problem I encountered was that I put my sleeping bag in an area that became a puddle about half an inch deep. Fortunately, my air mattress is 1.0 inch thick so I stayed above the water.

I may get beat up for talking about using plastic for a backpacking tarp on Backpacking Light, because it’s so cheap and flimsy, but here goes!

I have spent many nights sleeping under polyethylene tarps. They’re cheap, fairly lightweight, as waterproof as any other material, and possible to make robust enough to survive fairly bad weather. I’ve done about eight different designs and usually just use them on one trip of up to four nights.

I mainly use polyethylene tarps to prototype a design I want to verify before doing it in more expensive material. Such tarps would also be good for backpacking on the cheap, as you'd be able to equip four people for about $20 and some labor. In these economic times, frugal is popular.


I have always used 3 mil (0.003 inch thick) polyethylene, which is commonly used for protecting stuff while you’re painting. You can get a 10 x 25 ft piece from Home Depot for $10, which is enough for two or more tarps, depending on the tarps' size. The 3 mil weighs 2.0 oz/yd2, which is fairly light.

Just to experiment, I made a tarp out of 2 mil polyethylene, which weighs 1.4 oz/yd2. It held up in my backyard, through rain and wind, for more than a week before the duct tape reinforcing came off, which wasn’t even a polyethylene failure. Based on this test, I may use this lower weight sheeting instead.

As a comparison, silnylon, a common lightweight tarp material, is about 1.4 oz/yd2 and Cuben, the state of the art material, is 0.75 oz/yd2 for the thickness most commonly used for tarps.

MYOG: 3mm Plastic Tarps - 2
For guylines, I use Mason’s twine. (Shown: Mason’s twine, some of the slippery pale stuff that doesn’t work very well, and 16-oz coffee cup for scale.) I use this for all my tarps, food hanging line, ditty bag ties, etc. It’s fluorescent red to minimize running into or losing it. Home Depot sells it for $5 for 250 yards, which is enough for 30 tarps. The braided version works best for using a taut line hitch. It’s #18 thickness (0.0625 inch diameter). It weighs about an ounce for 25 feet, which is enough for most tarps.

Several other common guyline materials and weight for 25 feet:

  • Triptease: 0.7 ounce
  • Aircore 2: 0.25 ounce
  • Aircore 1: 0.1 ounce

I tried some similar line from Lowes, and it was thinner and slipperier so it didn’t work very well. The Home Depot line was a brighter fluorescent color. This could just be a particular lot and a different store, or a completely different product. I’ve also used twisted twine, but it comes untwisted too easily.

I use #0 size grommets on my tarps (0.25-inch diameter hole). Outdoor Wilderness Fabrics sells a grommet setter, hole punch, and 24 grommets for $15. I have a grommet setter similar to the OWF version, though mine is cast iron. You have to hammer on the die to squish the grommet down, and it’s a bit of a trick to get it right. You have to hammer the grommet enough so that it doesn’t rotate around in the plastic, but if you hammer it too much, the grommet's edges will cut the plastic. You should experiment first - hammer it too much so it cuts the edge to see what to avoid. I sometimes have to pry the grommet from the die with a screw driver.

I use readily available duct tape for reinforcement for guyline tieouts. One roll is enough for many tarps, and you probably don't even need to go buy some because you've got it lying around.

I have used two trees to hang a tarp, but it’s hard to find a location with a flat area between two trees. I like camping in alpine areas without many trees anyway, so I finally got a pole which works much better for a one-pole tarp configuration. It’s easier to find one tree next to a flat area. I don’t normally use trekking poles but those make excellent tent poles.

I use some Easton Aluminum tent poles from TentPole Technologies. Quest Outfitters is another good source. I get the 26-inch lengths and cut them down to about 21 inches for each section - 41-inch length as assembled. This is pretty flimsy and could collapse in strong winds, or could collapse if you run into it, but is quite lightweight - 1.5 ounces for the two-section pole. I’ve used this in 20 MPH winds a number of times and have gotten away with it. The tip fits into the #0 grommets. I whittled down the tip a little because it’s a tight fit.

Guyline and Pole Reinforcement

The first method I’ve used to attach guylines is to put a small pebble inside the corner of the plastic and tie around it with the guyline. If you’re not familiar with this, it can be handy in repairing a tarp that rips out in the field. I object to carrying pebbles, so I use 0.75-inch diameter styrofoam balls from the craft store.

MYOG: 3mm Plastic Tarps - 3
First put the ball in the corner and wrap around it with guyline.

MYOG: 3mm Plastic Tarps - 4
Tighten and tie a knot.

This is a strong connection and distributes the load to the plastic evenly. The only bad thing about this method is that it doesn’t pull on the precise corner of the tarp, but at a point a couple inches in from the corner, so there will be a few inches loose all around the tarp. Because it's not tensioned, it will flap in the wind. Also, this method doesn’t work very well as a connection to the sides of the tarp, only in the corners.

MYOG: 3mm Plastic Tarps - 5
Loose edges.

MYOG: 3mm Plastic Tarps - 6
The method I have used most often is duct tape for reinforcement with a grommet to run the guyline or pole tip through.

For example, last June I used a tarp in windy, rainy conditions for three nights at Burnt Lake and East Zigzag Mountain on Mount Hood in north central Oregon. Winds got up to about 20 MPH, and while the tarp held up fine, I noticed the duct tape slipped about 1/8 inch relative to the plastic. The adhesive on duct tape isn’t that great, and this wouldn’t last many more nights. Any suggestions on a better tape to use?

I wanted to find a way to attach guylines that would last a little longer than duct tape, so I constructed a simple test - 3 mil plastic, duct tape, and grommet on one side, guyline around foam ball on the other side. I then used it to hold 8 pounds (gallon milk jug of water).

MYOG: 3mm Plastic Tarps - 7
Test setup.

After about six hours, the duct tape slipped a little (which is what happened after three nights of backpacking in wet windy weather), and after twelve hours, the duct tape slipped off completely. This was my control... then I used the test setup to evaluate a few other methods.

First I put five staples through the duct tape/plastic. It held up fine for a week, so I think this would work well for a tarp on multiple trips.

Second, I tried something not requiring a grommet.

MYOG: 3mm Plastic Tarps - 8
First put the duct tape on one side of plastic and place knotted twine on the very edge of the plastic.

MYOG: 3mm Plastic Tarps - 9
Fold the duct tape over onto the other side of plastic, enclosing the knotted twine.

This held up for about a week in my test setup - the twine eventually slipped out of the duct tape. I also used it on a 2 mil plastic tarp that held up in rain and wind for a week before the duct tape slipped off, so this would make a reasonable connection for one trip. I might make the loose end longer and tie it to the main line with a taut line hitch so it won’t slip out.

I also used the test setup with 2 mil plastic. Foam ball worked best, staples in duct tape worked pretty well, no staple slipped off after about a day, knotted line without grommet held up for three days.

MYOG: 3mm Plastic Tarps - 10
I use a taut line hitch to tighten guylines. I don’t want to insult anyone by assuming they don’t know this knot, but just in case, here’s a taut line hitch loose.

MYOG: 3mm Plastic Tarps - 11
Taut line hitch tightened up. You have to really pull on the two loose ends (marked with red arrows) to tighten it up enough to hold on thin twine like this. After the tarp is set up and the lines are under tension, go over the taut line hitches one more time, really tightening them up. Also push the loops together on the two tight ends (not marked with arrows) to get the knot so it won’t slip.

This thin line is marginally thick enough to use a taut line hitch. You can always use tensioners instead of taut line hitch. For example, BPL's Aircore Nano Dyneema Spectra Guyline weighs 0.8 ounces for 50 feet of cord plus 12 tensioners, all for $15.99.

I use 0.34-inch Easton Aluminum poles, and the tips fit in a #0 (0.25-inch) grommet. This pole is a little light and might collapse, especially if you accidentally run your foot into it, but I’ve used it for years, with a 40-inch length, and it has never collapsed on me.

MYOG: 3mm Plastic Tarps - 12
If you don’t want to use a grommet to hold the pole, then use a guyline and make a clove hitch around the tip of the pole. This would work with a bigger pole, trekking pole, or stick.

Design Examples

Classic Pup Tent

MYOG: 3mm Plastic Tarps - 13
I used this style tent for my first backpack when I was 12 years old, and it is probably the most common tarp method. Basically, you just string a line between two trees or poles, put the tarp over it, and guy down the four corners

It works better if you have a guyline tieout at the middle of the tarp on each side at the ridgeline. Have a short guyline and tie it to the ridgeline line with a taut line hitch. This keeps the tarp stretched out along the ridgeline. Alternately, you can omit the ridgeline line that goes under the tarp, and instead go from both sides of the tarp to tree or pole, but this puts more stress on the guyline tieout, and if it fails, the tarp will collapse on you (this isn't a problem with fabrics so much as it can be with plastic).

I don’t really care for this design because it requires two poles, which is heavier, and if the wind blows into either end, then rain will blow in and get you wet. You can try variations, like lowering one end to reduce rain blowing in or making the tarp longer or wider. Adding a catenary ridgeline curve is out of the scope of a plastic tarp, but improves performance dramatically.

One Pole Tarp

MYOG: 3mm Plastic Tarps - 14
One pole tarp, in plastic.

This is what I have used more than anything else. On one end it’s like a pup tent, and on the other end, the two corners are about 40 inches apart and guylined to the ground. I added a “beak” at the pup tent end to reduce rain blowing in - folded the plastic and used duct tape/grommet to pull out with guyline. There’s duct tape with a grommet at the peak to put the pole through.

This uses less fabric than a pup tent because it’s narrower on one end. Only one end is open, which can allow rain in, which is bad, but only half as bad as a pup tent's two ends. It has only one pole which weighs less than a two-pole pup tent configuration. It is also easy to find a spot where you can use a simple tree instead of a pole, making it possibly a no pole design.

I’ve used various versions of this on about six trips of three or four nights each over the last couple years. I stayed fairly dry, and it held up pretty well to the wind. Obviously, you want to point the foot end into the wind to minimize rain blowing in, but the wind can always shift on you and defeat this idea.

A good size for one person is 40 inches wide at one end, 76 inches wide at the other end, and 9 feet long. Five square yards of fabric weighs about 10 ounces in 3 mil or 7 ounces in 2 mil or silnylon. Pole and stakes are maybe 4 ounces, so this makes for a pretty lightweight package.

MYOG: 3mm Plastic Tarps - 15
After successful polyethylene versions, I made one with silnylon to be lighter and more durable. I lengthened the beak and put in a zipper. I made catenary curves from the pole peak to each of the two corners on the low end.

MYOG: 3mm Plastic Tarps - 16
Head end view with zipper open. This weighs 11 ounces, plus 2 ounces for the pole and 1.25 ounces for the stakes.

Minimalist Tarp

I wanted to have an even lighter tarp that provides a better view from my sleeping bag for when there is only a small chance of a little rain or dew. I’ve slept without a tarp many nights when there was dew, and I slept fine and stayed dry inside, but then in the morning I have to dry things off and any gear also has to be dried off.

My idea is to have a tarp 44 inches wide guyed to the ground and 76 inches wide with two poles on the other end, 6 feet long. This only covers the top half of my sleeping bag, but my bag is water resistant - good enough for dew or slight rain. If it’s continuous hard rain, I’ll get wet.

MYOG: 3mm Plastic Tarps - 17
In 3 mil polyethylene it weighs 7 ounces. The poles weigh 3 ounces. The stakes weigh 1 ounce. I used this on one trip, and I was okay with it. I really like how I can see out of it almost as well as no tarp at all, but it isn't wind resistant.

MYOG: 3mm Plastic Tarps - 18
I liked it enough to make a version with polyester spinnaker cloth from Seattle Fabrics. I lengthened it a little to 7.5 feet.

MYOG: 3mm Plastic Tarps - 19
I tried it one night. When the winds got more than 20 MPH it was really noisy so I just took it down. It would help to have catenary curves on the two ridges.

The fabric is advertised as 0.75 oz/yd2, but I weighed it as 1.1 oz/yd2. It weighs 7 ounces, plus 3 ounces for poles and 1 ounce for stakes. I’ll play with this on a few trips to see if I like it, and probably find some modification to keep me busy.


If you enjoy making your own gear but hate making mistakes on expensive performance fabrics, get familiar with polyethylene. You can try several variations before making your first cut on the pricey stuff, and it's even sturdy enough for field testing.


"MYOG: 3mil Plastic Tarps," by Jerry Adams. (ISSN 1537-0364)., 2011-02-08 00:00:00-07.


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MYOG: 3mm Plastic Tarps
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Erik Danielsen
(er1kksen) - F

Locale: The Western Door
Oldschool on 02/09/2011 14:24:11 MST Print View

Come to think of it, this reminds me of a REALLY old outward bound video we watched in an Outdoor Education class I took. It was at a camp up in the Rockies, and each student went on a solo trip for a couple days sometime during the course of the program. Their state-of-the-art shelter was a piece of plastic sheeting (like these) draped over a ridgeline strung between two objects, with rocks used the same way as the styrofoam balls here to guy out the corners.

Sometimes you've got to step back and give the staying power of the low-tech some appreciation.

Jason Webb
(nikeman240) - MLife
silnylon version question on 02/12/2011 14:54:41 MST Print View

Do you have some pictures of where the pole meets the tarp? I'm working on making a tarp tent and haven't figured out the best way to reinforce the area where the pole meets the fabric (the peak). If anybody has any ideas , this would be greatly appreciated. I will post a full write up on my new tent after I get it completed just in case anybody wants to copy. ;)

Warren Greer
(WarrenGreer) - F

Locale: SoCal
hmmmm on 02/12/2011 18:09:48 MST Print View

Retiredjerry, great article. Some neat enginuity here. Thanks for sharing. I bet it sparks some ideas in the tent makers that frequent this site. Well done.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
re on 02/13/2011 17:00:22 MST Print View

Just got back from trip on beach of Olympic Peninsula - great place for winter trip - too busy in summer.

I'm surprised there was so much feedback - not made of Cuben or anything.

I'll have to try clear 3M tape next time, I think that might work better than duct tape. Or Gorilla Tape - there's so little used the weight probably doesn't matter.

Tyvek would probably work, I've only used it a little as a ground cloth. Is it wide enough for a tarp without having to sew pieces together? The beauty of poly is they make it in huge sheets.

There are three seams on my catenary curve silnylon tarp. The two ridgelines are cat curves. I keep playing with this. Currently I have a short center pole at the bottom - the two ridges with cat curves don't make sense but it doesn't seem to make any difference. What I should have done is make the tarp with two pieces and one seam down the center, same as other similar tarps, like the Cuben one that BPL sells.

Sheet bend at corners - then the edges of the tarp aren't under tension so they flap around a little, but so what I guess.

I have some bubble wrap, not sure yet what I'll make out of it, maybe a vest, 3M tape should be of use.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
peak reinforcement on 02/13/2011 17:06:50 MST Print View

Jason, I don't quite understand your question

The last three pictures show a pole through a grommet at the edge of the tarp.

Somewhere in the middle it has a closeup of pole without grommet. That's a pretty common way to do it, I believe.

What do you mean by the peak of a tarp tent?

Ronald Probst
Re: MYOG plastic tarps--another application on 02/21/2011 12:51:29 MST Print View

For those who, like me, don't make their own gear, this approach is useful to "prototype" manufacturers' shaped tarps. I'm just at the height where reviewers say "taller people may find this setup confining" so I like to "try before I buy". Manufacturer dimensions plus BPL review measurements, and a little geometry, enable a layout on sheet plastic. Straight lines and flat panels are good enough for this "fit check". These have just been backyard try-outs, but enough to eliminate a couple of purchases that I probably wouldn't have been happy with, and find out what works for my height even if it's heavier.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
Re: Re: MYOG plastic tarps--another application on 02/21/2011 13:12:28 MST Print View

Another thing you can try, is to just have twine where the ridgeline and corners are to get an idea if it's big enough,

easier than doing a plastic sheet

Henk Smees
(theflyingdutchman) - MLife

Locale: Spanish Mountains
That's what I did on 02/21/2011 13:41:31 MST Print View

As Jerry suggests, I use very thin sewing thread if I want to know how the dimensions will come out when I start with a new project.

This is a picture of the front-extension I was going to make for my GoLite Lair 1. I hope the thread is visible.

Avance Lair 1

Edit: to have a bit more contrast in picture - as I supposed, the lines where hardly visible (hope it's better now).

Edited by theflyingdutchman on 02/21/2011 13:48:05 MST.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
re on 02/21/2011 14:02:28 MST Print View

Exactly - I can see the threads - nice picture

Mariano Barrera
(bcm4066) - F
great job Jerry on 03/24/2011 00:17:35 MDT Print View

thanks for taking the time to share this.

i work in construction so i have miles of that line! and i'll be replacing my tent strings for this..

i'll def try the 3 mil plastic shelter... ! thanks again

Michael Witteveen
(Wittefish) - M

Locale: West Michigan
Tape on 02/06/2014 13:31:08 MST Print View

I've used 3M packing tape, but prefer Tyvek Tape if available. That stuff is pretty much permanent, just make sure you stick it in the right place the first time, it doesn't like to let go!

James Montgomery

Locale: Shasta County
Simplicity on 03/25/2014 14:19:55 MDT Print View

This is a very cool article. Nice to know there are other cheap/light freaks out there. I use a piece of plastic (8x12 in the winter) and drape it over a tautline, as shown above, only I leave 3-4 feet on the ground for a ground cover. Big rocks hold the ground cover in place, and the two corners on the other side of the line get tied out with sheet bends- or sometimes just held down with rocks. Under 4 ounces in 3 mil, according to the math above. One of these days I should weigh mine.
Not a perfect cover, but it will get you thru a storm. Yeah, you need to think about where you set up camp, but that's just good sense. Most of the time I would rather look at the stars, anyway, and the plastic is just a ground cover.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
Re: Simplicity on 03/25/2014 14:39:29 MDT Print View

That's funny, I figured this subject was so lame nobody would be interested : )

James Montgomery

Locale: Shasta County
Wrong on 03/25/2014 14:58:28 MDT Print View

Quite the opposite. Consumerism is lame. Good gear is important, but campcraft rules!
By the way, I've been at this awhile, and a lot of what I read seems written by tenderfeet. Thanx for a competent article.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
Re: Wrong on 03/25/2014 15:08:45 MDT Print View

The other thing is people's comments - lots of other ideas as good as the article